Clashes in Syria on Thursday killed nearly 170 people, mainly civilians, on the deadliest day since a ceasefire came into force, the Syrian Observatory for Human Rights said, as Russia acknowledged that it was trying to send repaired combat helicopters to Syria.

“It’s the bloodiest day since the start of the ceasefire (on April 12) and one of the bloodiest since the start of the revolt against the Syrian regime,” Observatory director Rami Abdul Rahman told AFP.

The day’s violence had killed at least 104 civilians, 54 soldiers and 10 rebel fighters, according to the toll compiled by the London-based organization, based on the reports of activists inside the country.

The heaviest losses were in the central region of Homs, where 31 civilians and a rebel fighter died; and in the opposition bastion of Duma, near Damascus, where 30 civilians died.

In the southern region of Deraa, 24 civilians -- including two children -- and five rebels were killed. Those killed elsewhere in Syria included a young girl, who died in the northwestern city of Idlib, the Observatory added.

ICRC fails to enter Homs

A girl wounded by shelling is treated at a mosque in Dael near the Syrian city of Deraa. (Reuters)

Aid workers hoping to evacuate trapped civilians and the wounded were unable to enter hard-hit areas of the Syrian city of Homs on Thursday due to shooting and an “unclear” security situation, the International Committee of the Red Cross (ICRC) said.

Government forces and rebels had both agreed on Wednesday to an ICRC request for a truce for humanitarian reasons after more than 10 days of intense fighting.

But when a team from the ICRC and Syrian Arab Red Crescent headed to the old city of Homs on Thursday morning, they heard shots, a spokesman said. The Syrian army shelled central districts of the city on Thursday, residents said.

“After having attempted to go into the old city of Homs this morning, the team decided to turn back to Homs city due to shooting. We could not identify the source of the shooting,” ICRC spokesman Hisham Hassan told Reuters on Thursday evening.

“Later on, the team concluded that the security situation was too unclear for us to go in,” he said. “The team has now returned to Damascus.”

The ICRC, the only international agency to deploy aid workers in Syria, remained in touch with government forces and opposition groups, he said.

Homs is the center of the 15-month revolt against President Bashar al-Assad whose forces are intensifying efforts to crush the uprising.

More than 15,000 people have been killed since the revolt against Syrian President Bashar al-Assad’s regime began in March 2011, according to Syrian opposition groups.

The United Nations says more than 10,000 people have been killed by Assad’s forces during the conflict. The government says at least 2,600 members of the military and security forces have been killed by what it characterizes as a plot by foreign-backed “Islamist terrorists” to bring it down.

Russia acknowledges sending helicopters to Syria

Russian Foreign Minister Sergei Lavrov. (File photo)

Meanwhile, Russia acknowledged on Thursday that it was trying to send repaired combat helicopters to Syria and said it would continue to carry out arms contracts with President Assad’s government despite Western and Arab criticism.

Foreign Minister Sergei Lavrov also made clear Russia and the United States remain at odds over a solution in Syria after a meeting between Presidents Barack Obama and Vladimir Putin, saying Assad’s exit cannot be a precondition for a political process.

On the sidelines of an economic forum in St. Petersburg, where Putin courted foreign investment, Lavrov said that the Alaed, a cargo ship that changed course this week after losing its insurance cover off Scotland, was carrying weapons to Syria.

Britain’s foreign minister Williams Hague said on Tuesday that the Curacao-flagged vessel had apparently headed back toward Russia after a London-based insurer withdrew coverage when informed of allegations it was carrying weapons.

The ship was carrying air defense systems, which can be used only for repelling foreign aggression and not against peaceful demonstrators, and it was carrying three repaired helicopters

Lavrov

Lavrov defended the abortive delivery and lashed out at the West over the incident, saying that the weapons could not be used against civilians protesting Assad’s rule and that the insurance company had no right to withdraw coverage.

“The ship was carrying air defense systems, which can be used only for repelling foreign aggression and not against peaceful demonstrators, and it was carrying three repaired helicopters,” Lavrov told Ekho Mosvky radio.

U.S. officials have called Russian arms deliveries to Syria reprehensible, and a senior Arab League official was quoted as saying in Russia on Thursday that “any assistance in aiding violence should be stopped.”

There is no full U.N. embargo of Syria, in part because Russia holds veto power as a permanent U.N. Security Council member.

“I will repeat: We are not violating anything, and we will continue to fulfill our contractual obligations,” Lavrov said, according to Reuters.

He said the helicopters, made in the Soviet era, had been repaired under a 2008 contract and shipped in dismantled form, adding that it would take at least three months to assemble them.

“And so to say that the Russians were bringing helicopters that could be used against peaceful demonstrators is a rather slanted position aimed to whip up passions and cast Russia in a bad light,” Lavrov said.

Syria is Moscow’s firmest foothold in the Middle East, buys weapons from Russia worth billions of dollars, and hosts the Russian navy’s only permanent warm water port outside the former Soviet Union.

Russia has used its Security Council veto to dilute Western efforts to condemn Assad and secure his exit from power, arguing that it is not up to outsiders to decide the political matters of sovereign states.